WASHINGTON (Reuters) - The U.S. Agriculture Department has issued a public health warning about raw ground beef products after dozens of people in the Northeast became ill with salmonella infections, a spokesman said on Friday.

The Centers for Disease Control and Prevention is investigating a salmonella outbreak of at least 37 cases in Connecticut, Maine, Massachusetts, New Hampshire, New York and Vermont.

Health officials said many of the people who became ill reported eating ground beef, and some ate the meat raw.